Currently, in a system in the communications field, in order to improve system reliability and improve a service processing capability, an existing load sharing device generally has an active/standby mode and a load sharing mode. In the active/standby mode, only one active unit (including a management control unit and a forwarding unit) works in a load sharing apparatus, and remaining one or more standby units (including a management control unit and a forwarding unit) perform hot backup or cold backup. When a fault occurs on the active unit, the standby unit can perform switching within a short period of time, to ensure a normal service. In the load sharing mode, multiple management control units and forwarding units can work together and undertake service processing together. In this case, no idle resource exists, so that utilization of bandwidth resources of the system is maximized.
An existing load sharing apparatus mainly has the following two manners:
1. A management control unit and a forwarding unit do not share a board, that is, the management control unit and the forwarding unit are physically separated.
2. A management control unit and a forwarding unit share a board and are located on a same board, and multiple identical boards implement a distributed load sharing function.
During implementation of the present invention, the inventors find that an existing load sharing method has a problem of low data transmission reliability.